diff --git a/src/main/java/org/tikv/common/exception/RegionException.java b/src/main/java/org/tikv/common/exception/RegionException.java
index d94b410519..3a8dd97737 100644
--- a/src/main/java/org/tikv/common/exception/RegionException.java
+++ b/src/main/java/org/tikv/common/exception/RegionException.java
@@ -24,7 +24,7 @@ public class RegionException extends TiKVException {
   private final Error regionErr;
 
   public RegionException(Error regionErr) {
-    super("Region Exception occurred" + regionErr.getMessage());
+    super("Region Exception occurred " + regionErr.getMessage());
     this.regionErr = regionErr;
   }
 
diff --git a/src/main/java/org/tikv/common/operation/KVErrorHandler.java b/src/main/java/org/tikv/common/operation/KVErrorHandler.java
index 35631e3dbc..55bbdef44e 100644
--- a/src/main/java/org/tikv/common/operation/KVErrorHandler.java
+++ b/src/main/java/org/tikv/common/operation/KVErrorHandler.java
@@ -123,9 +123,7 @@ public class KVErrorHandler<RespT> implements ErrorHandler<RespT> {
   @Override
   public boolean handleResponseError(BackOffer backOffer, RespT resp) {
     if (resp == null) {
-      String msg =
-          String.format(
-              "Request Failed with unknown reason for region region [%s]", recv.getRegion());
+      String msg = String.format("Request Failed with unknown reason for [%s]", recv.getRegion());
       logger.warn(msg);
       return handleRequestError(backOffer, new GrpcException(msg));
     }
diff --git a/src/main/java/org/tikv/common/util/Batch.java b/src/main/java/org/tikv/common/util/Batch.java
index 5f8e63886e..2c9f161bf3 100644
--- a/src/main/java/org/tikv/common/util/Batch.java
+++ b/src/main/java/org/tikv/common/util/Batch.java
@@ -56,7 +56,7 @@ public class Batch {
   }
 
   public BackOffer getBackOffer() {
-    return backOffer;
+    return ConcreteBackOffer.create(backOffer);
   }
 
   public TiRegion getRegion() {